A conventional portable telephone lists many items corresponding to various functions in a line on a display unit which is a liquid crystal display, executes the processing corresponding to a desired item selected and confirmed by a user with an arrow key or the like, and displays the processing result.
In this case, because all items arranged in a line are hard for a user not only to see but also to find out a desired item, the menus are classified according to functions or mode and the portable telephone displays them in the form of menus on the display unit.
By the way, in such a portable telephone that menus are created through classification into modes, the user firstly needs to display on the display unit a menu corresponding a desired mode before selecting an item.
In this case, the user has to confirm the menu whether it is the one which has been selected by himself because the menus created through the classification have all the same format. The portable telephone, however, has the display unit of a limited size and therefore, displays the title letters of each item in a small size, which causes problems in that the user can not judge immediately whether the menu being displayed corresponds to the desired mode and as a result, its operability is no good.
Further, in such a portable telephone, although a selected item enclosed by a frame of a predetermined shape is displayed in order to visually differ from the unselected items, the selected item and unselected items have the same luminance level and the same color tone, which causes a problem in that the selected item and the unselected items are difficult to distinguish at one moment. On the other hand, some portable telephones display an selected item in an inverse video in order to visually differ from the other unselected items, which causes a problem in that the title letters of the selected item may be hard to see due to the color of the inverted display area.
Furthermore, a conventional portable telephone, as shown in FIG. 21(A), displays plural items corresponding to various functions of the portable telephone on a display unit 100 which is a liquid crystal display, executes the processing corresponding to a desired item selected and confirmed by a user, and displays the processing result.
In this case, the portable telephone displays a selection frame (hereinafter, referred to as a cursor) 102 of a given shape so as to enclose one item, on the display unit 100, in order to allow a user to select a desired item by moving the cursor 102 up and down with an arrow key or the like.
By the way, such portable telephone has a limited size of the display unit 100 and therefore, displays only some (5 items, for example) out of the plural items on the display unit 100.
In the case where hidden items (these are referred to as upper undisplayed items 103) exist above the displayed items, the portable telephone displays an upward triangle icon 104 at the top end of the display unit 100 in order to inform a user of the existence of the upper undisplayed items 103.
Similarly, in the case where hidden items (these are referred to as lower undisplayed items 105) exist following the displayed items, the portable telephone displays a downward triangle icon 106 at the bottom end of the display unit 100 in order to inform the user of the existence of the lower undisplayed items 105.
Then, in a situation where the upper undisplayed items 103 exist and the cursor 102 appears at the first end of the display unit 101 as shown in FIG. 21(B), when the cursor 70 is to be moved upward further, the portable telephone moves not the cursor 102 but all items together downward (in a direction opposite to the movement operation) by one item in order to display an item 101B, which has been hidden, in the cursor 102 so that the item 101B is selectable as shown in FIG. 21(C).
Similarly, in a situation where the lower undisplayed items 105 exists and the cursor 102 appears at the bottom end of the display unit 100, when the cursor 70 is to be moved downward further, the portable telephone moves not the cursor 102 but all items together upward (in a direction opposite to the movement operation) by one item in order to display an item 101H, which has been hidden, the cursor 102 so that the item 101H is selectable as shown in FIG. 21(D).
In this way, the portable telephone allows the user to select an item by sequentially display items, which are more than the number of items which can be displayed on the display unit 100 at a time, on the display unit 100.
By the way, such a portable telephone does not display an upper undisplayed item 103 or an lower undisplayed item 105 which is selectable next by operating the cursor 102, on the display unit 100 when the cursor 102 appears at the top end or the bottom end of the display unit 100, which causes a bad-operability problem because the user can not know which item is selectable next.
In addition, when the cursor 102 being displayed at the top end of the display unit 100 is to be moved upward or the cursor 102 being displayed at the bottom end of the display unit 100 is to be moved downward, such portable telephone moves all items in a direction opposite to the movement operation. It means that the direction of the inputted operation and the movement direction of the screen display are not the same, and the cursor 102 itself does not move, which causes a bad-operability problem in that it is hard for the user to recognize whether his movement operation has been surely entered.